LinuxQuestions.org
Visit the LQ Articles and Editorials section
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Desktop
User Name
Password
Linux - Desktop This forum is for the discussion of all Linux Software used in a desktop context.

Notices



Reply
 
Search this Thread
Old 04-06-2011, 07:01 PM   #1
Gullible Jones
Member
 
Registered: Apr 2011
Posts: 142

Rep: Reputation: 10
Unhappy KDE4... Why the sluggish performance? [SOLVED for now]


Everywhere I look, people rave about how fast KDE4 is. I've even seen reports that it works great on an Eee700 netbook. So I try it on my Eee1005HAB...

And it's slower than molasses.

Windows resized in jerks. Menus lag. Window redraws take 2-3 seconds. I can tell windows to only show frames while being resized, and still see the redraws. It makes Windows Vista look like a speed demon.

I've tried a number of tweaks. Setting Qt to the "Low resolution and low CPU" setting... Skipping ARGB visuals... Disabling IPV6... Switching to the raster graphics engine... Disabling the Composite extension... Even switching in Openbox as a window manager (which messes up the Plasma desktop). None of it works at all. Everything's still incredibly slow, on hardware that really should not have a problem with it. And this is without compositing. With compositing, it's like a slide show.

What am I doing wrong here? There must be something I'm missing...

Last edited by Gullible Jones; 05-01-2011 at 07:52 PM.
 
Old 04-06-2011, 11:34 PM   #2
jlinkels
Senior Member
 
Registered: Oct 2003
Location: Bonaire
Distribution: Debian Lenny/Squeeze/Wheezy/Sid
Posts: 4,182

Rep: Reputation: 508Reputation: 508Reputation: 508Reputation: 508Reputation: 508Reputation: 508
It looks like the wrong graphic driver. What VGA card do you have in that eeePC. Ironically, on my wife's eeeePC KDE runs very smooth. Start a console, issue top command and check whether the CPU usage of xorg rockets to 100% when you move something. If so, you probably are using th wrong graphic driver.

jlinkels
 
Old 04-07-2011, 04:08 AM   #3
cascade9
Senior Member
 
Registered: Mar 2011
Location: Brisneyland
Distribution: Debian, aptosid
Posts: 3,718

Rep: Reputation: 904Reputation: 904Reputation: 904Reputation: 904Reputation: 904Reputation: 904Reputation: 904Reputation: 904
Quote:
Originally Posted by Gullible Jones View Post
Everywhere I look, people rave about how fast KDE4 is. I've even seen reports that it works great on an Eee700 netbook. So I try it on my Eee1005HAB...
I used KDE4.X, and while I like it a lot I'd never go on about how fast it is. IMO KDE4.X is not fast at all. Sure, with decent hardware its not slow, but for speed a *box, Lxde or Xfce are what you should be looking at. IMO KDE4.X needs a decent video card, and a fairly nice CPU.

However some people out there might not notice what I do, so maybe there are folks around who think that KDE4.X is fast. If thats what they think, then I'm not going to convince them they are wrong....

I would guess that jlinkels is right, its video card related. Window redrawing shouldnt take 2-3 seconds.

BTW, the video chip is GMA950 from, what I can see. IIRC there has been some issues with the GMA950 with linux generally. GMA is a long, long way from a decent video card though. No support for hardware transform and lighting, or shaders. I've tried running KDE4.X on (proper) GPUs, not intel video chips and and it can still be sluggish with older video hardware. Still, it shouldnt be that slow.
 
Old 04-07-2011, 06:47 AM   #4
salasi
Senior Member
 
Registered: Jul 2007
Location: Directly above centre of the earth, UK
Distribution: SuSE, plus some hopping
Posts: 3,915

Rep: Reputation: 777Reputation: 777Reputation: 777Reputation: 777Reputation: 777Reputation: 777Reputation: 777
Quote:
Originally Posted by Gullible Jones View Post
Everywhere I look, people rave about how fast KDE4 is.
The only people I've seen saying that KDE 4 is fast (not just not slow, but actually fast) have been Windows Vista users, and they may have, errr, unusual expectations in this area.

having said that
  • KDE 4.x is heavy on memory, and how bad that is depends on how much memory you have and whether you are doing memory intensive stuff on top of kde itself. does the disk drive light blink constantly and have you had a look at the system monitor (ksysguard) to see if anything shows up?
  • On the same theme, you'll probably see memory leaks with earlier versions and extended uptimes. Does it slow down over time and does it get better (somewhat) after a reboot?
  • In general, early versions of kde 4. are a bit crap. If you are using, say, 4.2.x or earlier, then try something later. (You really need to be in the 4.3.x series, or later, for usability.)
  • And even more particular, the redesign of the video system at 4.6 is probably advantageous. and a bit more efficient, but I do find that I have to use Xrender rather than OpenGL for compositing, but ymmv.
  • ...and even if you have everything humming along nicely in KDE4, it is unlikely that you will outpace kde3. Or XFCE. Or enlightenment. Or any of the lighter alternatives.
 
Old 04-07-2011, 10:12 AM   #5
jlinkels
Senior Member
 
Registered: Oct 2003
Location: Bonaire
Distribution: Debian Lenny/Squeeze/Wheezy/Sid
Posts: 4,182

Rep: Reputation: 508Reputation: 508Reputation: 508Reputation: 508Reputation: 508Reputation: 508
This doesn't really contribute to the discussion (sorry about that) but I do have to vent my frustration.

BTW salasi is completely right on what he is saying that at best KDE4 is not slow, as opposed to fast.

This week I upgraded one of my older laptops to Debian Squeeze including KDE4.4.5. The laptop has an ATI Radeon R300 card. Driver is installed correctly, compositing works, etc. The only thing which is really sluggish is the resizing of windows, about 3-4 fps. Other graphical effects like wobbly windows, magic lamp effect when closing windows and cube rotation are smooth.

However, sometimes when I rotate the cube, it is slow, frame rate goes down considerably, and motion becomes jerky. For this purpose I opened a konsole and showed top. Xorg was running about 25% processor capacity during cube rotation. Then a message popped up: It seems that animation runs slow. Therefor compositing has been disabled. So I enabled it again, and presto! cube rotation was smooth again, while processor load of Xorg increased to 29%.

Once more I was wondering why KDE4 is still loaded with bugs after 4 years of development. If KDE4 is complicated, in fact too complicated to get it right, they should not have completely disposed KDE3. After all, KDE4 seems to imitate Vista as much as possible. Not just in appearance but as well in speed, bugginess, user frustration and being on the wrong track. It had not been necessary to follow Microsoft. Next step is KDE7?

jlinkels

Last edited by jlinkels; 04-07-2011 at 10:14 AM.
 
Old 04-07-2011, 01:28 PM   #6
Gullible Jones
Member
 
Registered: Apr 2011
Posts: 142

Original Poster
Rep: Reputation: 10
Yeah, the graphics hardware is Intel GMA945. IOW, garbage.

But GTK applications don't care that the GPU is rubbish, and redraw quite speedily. Same with pure Qt apps... And, for that matter, with KDE apps running outside the desktop environment. Try running Dolphin under an Openbox session, for instance.

So why does running stuff in the KDE desktop magically make it sluggish?
 
Old 04-18-2011, 05:33 PM   #7
Gullible Jones
Member
 
Registered: Apr 2011
Posts: 142

Original Poster
Rep: Reputation: 10
Okay, what I've found so far:

- Disabling sound notifications makes menus no longer sluggish, for some reason. Supposedly this is a bug in Phonon's Xine backend? Weird.

- Making windows show only as frames when moving/resizing hides most of the sluggish redraws. Unfortunately, it also creates occasional graphical artifacts where frames overlap window borders. Disabling the Composite extension helps, but doesn't remove the artifacts entirely - if anyone can tell me how to get rid of those, that'd be nice... TIA.
 
Old 05-06-2011, 12:06 AM   #8
Gullible Jones
Member
 
Registered: Apr 2011
Posts: 142

Original Poster
Rep: Reputation: 10
Okay, it turns out I'd been doing things wrong when trying to disable ARGB visuals. The correct environment variable to export is

KDE_SKIP_ARGB_VISUALS=1

This makes things ludicrously faster, so I'm going to mark this as solved.
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
(ubuntu 9.10) XP in virtualbox, sluggish performance Michio Linux - Software 1 01-07-2010 10:34 PM
Sluggish performance with Slackware 12.2 2.6.27.7-smp on Gigabyte GA-8S649MF kslen Slackware 30 05-24-2009 06:52 PM
sluggish and poor performance from ATI Mobility P/M with Kubuntu 7.04 Jay Jay Linux - Laptop and Netbook 4 08-31-2007 10:44 PM
Very sluggish performance bene223 Linux - Newbie 21 06-27-2006 01:46 AM
Sluggish performance w/ RH 7.3 theonlylivinggo Linux - Newbie 0 02-15-2004 09:13 PM


All times are GMT -5. The time now is 10:03 PM.

Main Menu
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
identi.ca: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration